This invention relates generally to electronic circuits and specifically to amplifier circuits for use in solid state communications equipment whereby a small percentage of nonlinearity is tolerated but size is a critical factor.
Various manufacturers have sold various general purpose operational amplifiers for solid-state analog circuit operation. These circuits usually are concerned with low distortion, input sensitivity, rise time, slew rate and frequency and transient response characteristics, etc. over a relatively broad operational range.
While circuits can contain as many as twenty (20) silicon devices (transistors), they, more often, contain at least eight-to-ten (8-10) of them, as well as numerous resistors and diodes. When the operating requirements upon an operational amplifier are limited to a specific range and to limited space requirements, these prior art operational amplifiers provide too big and too costly a design choice.
What is desired is an operational amplifier which can be used in solid-state circuits such as those generating color signals for television in driving color guns and which take up and use a minimum amount of circuitry.
An object of this invention is to provide an operational amplifier which uses a minimum amount of circuitry.
A second object of this invention is to provide such an operational amplifier which exhibits less than 5% distortion when operated open loop over an output range of from 1.5 to 7.5 volts.
A further object of this invention is to provide such an amplifier which can be powered by a 12-volt supply and which is highly linear under closed loop circuit connection.
An even further object of this invention is to provide such an amplifier with a maximum output voltage range of 1 to 8 volts.